If you are at all suggesting that esf would become a single player game, then no. It's been suggested before. If you are sayying they should use some sought of game development engine tools then no, even that would be to much work as everything would have to be redone.
ESF is a Half-Life mod, and as such, Half-Life is the foundation of ESF.
What you're asking is equivalent to taking an elevator to the 20th story of a building, then saying "I want this on the ground level!" Okay, we'll rip it from the rest of the building and drop it onto the street. Everything'll work fine!